抄録
The localization of tyrosine hydroxylase (TH) -immunoreactive (IR) (TH-IR) neurons, which are transiently observed in the anterior olfactory nucleus (AON) of the mouse, was studied. A double-labelling method was used with antibodies against TH, L-3, 4-dihydroxyphenylalanine (DOPA), phenyletha-nolamine-N-methyltransferase (PNMT), γ-aminobutyric acid (GABA), calretinin (CR) and calbindin-D28k (CB). When the total number of TH-IR neurons observed in all regions of the AON obtained from 10- to 14- day-old mice was set at 100%, 30% of TH-IR neurons were observed in the lateral (AOL), 25% in the dorsal (AOD), 20% in the ventral (AOV), 15% in the medial (AOM) and 5% in both the posterior (AOP) and external (AOE) regions. Approximately 40% of the TH-IR neurons in the AOL to the AOV regions also exhibited GABA immunoreactivity. This corresponds to 20% of the total number of TH-IR neurons observed in all regions of the AON, and also corresponds to 12% of the total number of GABA-IR neurons observed in all regions of the AON. However, TH-IR neurons did not exhibit concomitant PNMT, CR, and CB immunoreactivities. These findings suggest that the TH-IR neurons in the AON of the mouse, a proportion of which is also GABA-IR, may function as a source of neuromodulators for the postnatal growth of GABA-IR neurons.